Composite Blocking List
In computer networking, the Composite Blocking List is a DNS-based Blackhole List of suspected E-mail spam sending computer infections.
Overview
The CBL takes its source data from very large spamtraps/mail infrastructures, and only lists IPs exhibiting characteristics such as:- Open proxies of various sorts
- Worms/viruses/botnets that do their own direct mail transmission, or are otherwise participating in a botnet.
- Trojan horse or "stealth" spamware.
Entries automatically expire after a period of time. The CBL does not provide public access to gathered evidence. CBL data are used in Spamhaus XBL list.